When you think of great works of architecture, you might think of legendary names like Frank Lloyd Wright and his stunning Fallingwater house in rural Pennsylvania, marrying nature and modern design. Or the defining feature of Paris, the Eiffel Tower. Or the incredible designs of Antoni Gaudí, dotted throughout Barcelona.

Great architects take pride in their ability to marry beauty and functionality in design. But in recent years, the phenomenon of 'defensive architecture' or 'hostile architecture' has become a feature of urban design. In both intention and design, it has proved highly controversial, as Joe Duffy discovered on today’s Liveline, when he spoke to Anti-Austerity Alliance councillor Michael O’Brien.

“A journalist in the Dublin Enquirer called me a couple of days ago… about a tattoo parlour in Temple Bar, which had installed external sprinklers, which would normally be used for watering plants. Except there were no plants outside. It was reported by people who are homeless that it was a means of deterring rough sleepers.”

All of which cuts to the definition of defensive or hostile architecture as, 'a controversial urban design trend in which public spaces are constructed or altered to discourage people from using them in a way not intended by the owner.'

Michael O’Brien is not happy with the uptake of this particular design trend in Dublin, and took issue with this latest example in particular.

“I just think it’s particularly objectionable, but also dangerous as well, particularly on cold night, if you’re a rough sleeper.”

But answering the charge, Kevin McNamara, the manager of the tattoo parlour, had this to say.

“They are not designed to deter homeless people, we have no particular issue with homeless people. It is purely a safety concern. It’s been years of addict issues in this area, and around our studio. You come in in the morning, there is blood everywhere, faeces, syringes.”

Many people will be more familiar with the installation of spikes in certain areas outside buildings, whether on low window ledges or on the ground, to deter unwelcome occupation of those spaces. Kevin McNamara regards his sprinkler system as far better and more “humane”, although councillor Michael Ryan questions this.

One way or another, this particular tattoo parlour is not the first, nor will it be the last, to install measures such as these.

The issue with this particular parlour was brought to the attention of Michael O’Brien by Laoise Neylon, of the Dublin Inquirer, who also pointed to the fact that Dublin City Council have a waste management division trained with appropriate equipment to find and clear hazardous waste. If you have such a problem, you can contact them at 01-222 4242.

Dublin's Housing First Service (state funded and operated by PMVT and Focus Ireland) provides support and access to accommodation for persons who are rough sleeping. Please contact them directly on 086 8139015 or alternatively consult this website.: http://www.homelessdublin.ie/help-someone-who-sleeping-rough

And if you like to listen to the full interview, click here.